llvm-6502/utils/TableGen/FileParser.y.cvs
Chris Lattner cce56af911 Make sure to clear CurDefmPrefix = 0, otherwise stuff after a defm won't
parse right.  This fixes TableGen/MultiClass.td


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30037 91177308-0d34-0410-b5e6-96231b3b80d8
2006-09-01 22:07:27 +00:00

795 lines
23 KiB
C++

//===-- FileParser.y - Parser for TableGen files ----------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file implements the bison parser for Table Generator files...
//
//===----------------------------------------------------------------------===//
%{
#include "Record.h"
#include "llvm/ADT/StringExtras.h"
#include <algorithm>
#include <cstdio>
#define YYERROR_VERBOSE 1
int yyerror(const char *ErrorMsg);
int yylex();
namespace llvm {
struct MultiClass {
Record Rec; // Placeholder for template args and Name.
std::vector<Record*> DefPrototypes;
MultiClass(const std::string &Name) : Rec(Name) {}
};
static std::map<std::string, MultiClass*> MultiClasses;
extern int Filelineno;
static MultiClass *CurMultiClass = 0; // Set while parsing a multiclass.
static std::string *CurDefmPrefix = 0; // Set while parsing defm.
static Record *CurRec = 0;
static bool ParsingTemplateArgs = false;
typedef std::pair<Record*, std::vector<Init*>*> SubClassRefTy;
struct LetRecord {
std::string Name;
std::vector<unsigned> Bits;
Init *Value;
bool HasBits;
LetRecord(const std::string &N, std::vector<unsigned> *B, Init *V)
: Name(N), Value(V), HasBits(B != 0) {
if (HasBits) Bits = *B;
}
};
static std::vector<std::vector<LetRecord> > LetStack;
extern std::ostream &err();
/// getActiveRec - If inside a def/class definition, return the def/class.
/// Otherwise, if within a multidef, return it.
static Record *getActiveRec() {
return CurRec ? CurRec : &CurMultiClass->Rec;
}
static void addValue(const RecordVal &RV) {
Record *TheRec = getActiveRec();
if (RecordVal *ERV = TheRec->getValue(RV.getName())) {
// The value already exists in the class, treat this as a set...
if (ERV->setValue(RV.getValue())) {
err() << "New definition of '" << RV.getName() << "' of type '"
<< *RV.getType() << "' is incompatible with previous "
<< "definition of type '" << *ERV->getType() << "'!\n";
exit(1);
}
} else {
TheRec->addValue(RV);
}
}
static void addSuperClass(Record *SC) {
if (CurRec->isSubClassOf(SC)) {
err() << "Already subclass of '" << SC->getName() << "'!\n";
exit(1);
}
CurRec->addSuperClass(SC);
}
static void setValue(const std::string &ValName,
std::vector<unsigned> *BitList, Init *V) {
if (!V) return;
RecordVal *RV = CurRec->getValue(ValName);
if (RV == 0) {
err() << "Value '" << ValName << "' unknown!\n";
exit(1);
}
// Do not allow assignments like 'X = X'. This will just cause infinite loops
// in the resolution machinery.
if (!BitList)
if (VarInit *VI = dynamic_cast<VarInit*>(V))
if (VI->getName() == ValName)
return;
// If we are assigning to a subset of the bits in the value... then we must be
// assigning to a field of BitsRecTy, which must have a BitsInit
// initializer...
//
if (BitList) {
BitsInit *CurVal = dynamic_cast<BitsInit*>(RV->getValue());
if (CurVal == 0) {
err() << "Value '" << ValName << "' is not a bits type!\n";
exit(1);
}
// Convert the incoming value to a bits type of the appropriate size...
Init *BI = V->convertInitializerTo(new BitsRecTy(BitList->size()));
if (BI == 0) {
V->convertInitializerTo(new BitsRecTy(BitList->size()));
err() << "Initializer '" << *V << "' not compatible with bit range!\n";
exit(1);
}
// We should have a BitsInit type now...
assert(dynamic_cast<BitsInit*>(BI) != 0 || &(std::cerr << *BI) == 0);
BitsInit *BInit = (BitsInit*)BI;
BitsInit *NewVal = new BitsInit(CurVal->getNumBits());
// Loop over bits, assigning values as appropriate...
for (unsigned i = 0, e = BitList->size(); i != e; ++i) {
unsigned Bit = (*BitList)[i];
if (NewVal->getBit(Bit)) {
err() << "Cannot set bit #" << Bit << " of value '" << ValName
<< "' more than once!\n";
exit(1);
}
NewVal->setBit(Bit, BInit->getBit(i));
}
for (unsigned i = 0, e = CurVal->getNumBits(); i != e; ++i)
if (NewVal->getBit(i) == 0)
NewVal->setBit(i, CurVal->getBit(i));
V = NewVal;
}
if (RV->setValue(V)) {
err() << "Value '" << ValName << "' of type '" << *RV->getType()
<< "' is incompatible with initializer '" << *V << "'!\n";
exit(1);
}
}
// addSubClass - Add SC as a subclass to CurRec, resolving TemplateArgs as SC's
// template arguments.
static void addSubClass(Record *SC, const std::vector<Init*> &TemplateArgs) {
// Add all of the values in the subclass into the current class...
const std::vector<RecordVal> &Vals = SC->getValues();
for (unsigned i = 0, e = Vals.size(); i != e; ++i)
addValue(Vals[i]);
const std::vector<std::string> &TArgs = SC->getTemplateArgs();
// Ensure that an appropriate number of template arguments are specified...
if (TArgs.size() < TemplateArgs.size()) {
err() << "ERROR: More template args specified than expected!\n";
exit(1);
}
// Loop over all of the template arguments, setting them to the specified
// value or leaving them as the default if necessary.
for (unsigned i = 0, e = TArgs.size(); i != e; ++i) {
if (i < TemplateArgs.size()) { // A value is specified for this temp-arg?
// Set it now.
setValue(TArgs[i], 0, TemplateArgs[i]);
// Resolve it next.
CurRec->resolveReferencesTo(CurRec->getValue(TArgs[i]));
// Now remove it.
CurRec->removeValue(TArgs[i]);
} else if (!CurRec->getValue(TArgs[i])->getValue()->isComplete()) {
err() << "ERROR: Value not specified for template argument #"
<< i << " (" << TArgs[i] << ") of subclass '" << SC->getName()
<< "'!\n";
exit(1);
}
}
// Since everything went well, we can now set the "superclass" list for the
// current record.
const std::vector<Record*> &SCs = SC->getSuperClasses();
for (unsigned i = 0, e = SCs.size(); i != e; ++i)
addSuperClass(SCs[i]);
addSuperClass(SC);
}
} // End llvm namespace
using namespace llvm;
%}
%union {
std::string* StrVal;
int IntVal;
llvm::RecTy* Ty;
llvm::Init* Initializer;
std::vector<llvm::Init*>* FieldList;
std::vector<unsigned>* BitList;
llvm::Record* Rec;
std::vector<llvm::Record*>* RecList;
SubClassRefTy* SubClassRef;
std::vector<SubClassRefTy>* SubClassList;
std::vector<std::pair<llvm::Init*, std::string> >* DagValueList;
};
%token INT BIT STRING BITS LIST CODE DAG CLASS DEF MULTICLASS DEFM FIELD LET IN
%token SHLTOK SRATOK SRLTOK STRCONCATTOK
%token <IntVal> INTVAL
%token <StrVal> ID VARNAME STRVAL CODEFRAGMENT
%type <Ty> Type
%type <Rec> ClassInst DefInst MultiClassDef ObjectBody ClassID
%type <RecList> MultiClassBody
%type <SubClassRef> SubClassRef
%type <SubClassList> ClassList ClassListNE
%type <IntVal> OptPrefix
%type <Initializer> Value OptValue IDValue
%type <DagValueList> DagArgList DagArgListNE
%type <FieldList> ValueList ValueListNE
%type <BitList> BitList OptBitList RBitList
%type <StrVal> Declaration OptID OptVarName ObjectName
%start File
%%
ClassID : ID {
if (CurDefmPrefix) {
// If CurDefmPrefix is set, we're parsing a defm, which means that this is
// actually the name of a multiclass.
MultiClass *MC = MultiClasses[*$1];
if (MC == 0) {
err() << "Couldn't find class '" << *$1 << "'!\n";
exit(1);
}
$$ = &MC->Rec;
} else {
$$ = Records.getClass(*$1);
}
if ($$ == 0) {
err() << "Couldn't find class '" << *$1 << "'!\n";
exit(1);
}
delete $1;
};
// TableGen types...
Type : STRING { // string type
$$ = new StringRecTy();
} | BIT { // bit type
$$ = new BitRecTy();
} | BITS '<' INTVAL '>' { // bits<x> type
$$ = new BitsRecTy($3);
} | INT { // int type
$$ = new IntRecTy();
} | LIST '<' Type '>' { // list<x> type
$$ = new ListRecTy($3);
} | CODE { // code type
$$ = new CodeRecTy();
} | DAG { // dag type
$$ = new DagRecTy();
} | ClassID { // Record Type
$$ = new RecordRecTy($1);
};
OptPrefix : /*empty*/ { $$ = 0; } | FIELD { $$ = 1; };
OptValue : /*empty*/ { $$ = 0; } | '=' Value { $$ = $2; };
IDValue : ID {
if (const RecordVal *RV = (CurRec ? CurRec->getValue(*$1) : 0)) {
$$ = new VarInit(*$1, RV->getType());
} else if (CurRec && CurRec->isTemplateArg(CurRec->getName()+":"+*$1)) {
const RecordVal *RV = CurRec->getValue(CurRec->getName()+":"+*$1);
assert(RV && "Template arg doesn't exist??");
$$ = new VarInit(CurRec->getName()+":"+*$1, RV->getType());
} else if (CurMultiClass &&
CurMultiClass->Rec.isTemplateArg(CurMultiClass->Rec.getName()+"::"+*$1)) {
std::string Name = CurMultiClass->Rec.getName()+"::"+*$1;
const RecordVal *RV = CurMultiClass->Rec.getValue(Name);
assert(RV && "Template arg doesn't exist??");
$$ = new VarInit(Name, RV->getType());
} else if (Record *D = Records.getDef(*$1)) {
$$ = new DefInit(D);
} else {
err() << "Variable not defined: '" << *$1 << "'!\n";
exit(1);
}
delete $1;
};
Value : IDValue {
$$ = $1;
} | INTVAL {
$$ = new IntInit($1);
} | STRVAL {
$$ = new StringInit(*$1);
delete $1;
} | CODEFRAGMENT {
$$ = new CodeInit(*$1);
delete $1;
} | '?' {
$$ = new UnsetInit();
} | '{' ValueList '}' {
BitsInit *Init = new BitsInit($2->size());
for (unsigned i = 0, e = $2->size(); i != e; ++i) {
struct Init *Bit = (*$2)[i]->convertInitializerTo(new BitRecTy());
if (Bit == 0) {
err() << "Element #" << i << " (" << *(*$2)[i]
<< ") is not convertable to a bit!\n";
exit(1);
}
Init->setBit($2->size()-i-1, Bit);
}
$$ = Init;
delete $2;
} | ID '<' ValueListNE '>' {
// This is a CLASS<initvalslist> expression. This is supposed to synthesize
// a new anonymous definition, deriving from CLASS<initvalslist> with no
// body.
Record *Class = Records.getClass(*$1);
if (!Class) {
err() << "Expected a class, got '" << *$1 << "'!\n";
exit(1);
}
delete $1;
static unsigned AnonCounter = 0;
Record *OldRec = CurRec; // Save CurRec.
// Create the new record, set it as CurRec temporarily.
CurRec = new Record("anonymous.val."+utostr(AnonCounter++));
addSubClass(Class, *$3); // Add info about the subclass to CurRec.
delete $3; // Free up the template args.
CurRec->resolveReferences();
Records.addDef(CurRec);
// The result of the expression is a reference to the new record.
$$ = new DefInit(CurRec);
// Restore the old CurRec
CurRec = OldRec;
} | Value '{' BitList '}' {
$$ = $1->convertInitializerBitRange(*$3);
if ($$ == 0) {
err() << "Invalid bit range for value '" << *$1 << "'!\n";
exit(1);
}
delete $3;
} | '[' ValueList ']' {
$$ = new ListInit(*$2);
delete $2;
} | Value '.' ID {
if (!$1->getFieldType(*$3)) {
err() << "Cannot access field '" << *$3 << "' of value '" << *$1 << "!\n";
exit(1);
}
$$ = new FieldInit($1, *$3);
delete $3;
} | '(' IDValue DagArgList ')' {
$$ = new DagInit($2, *$3);
delete $3;
} | Value '[' BitList ']' {
std::reverse($3->begin(), $3->end());
$$ = $1->convertInitListSlice(*$3);
if ($$ == 0) {
err() << "Invalid list slice for value '" << *$1 << "'!\n";
exit(1);
}
delete $3;
} | SHLTOK '(' Value ',' Value ')' {
$$ = (new BinOpInit(BinOpInit::SHL, $3, $5))->Fold();
} | SRATOK '(' Value ',' Value ')' {
$$ = (new BinOpInit(BinOpInit::SRA, $3, $5))->Fold();
} | SRLTOK '(' Value ',' Value ')' {
$$ = (new BinOpInit(BinOpInit::SRL, $3, $5))->Fold();
} | STRCONCATTOK '(' Value ',' Value ')' {
$$ = (new BinOpInit(BinOpInit::STRCONCAT, $3, $5))->Fold();
};
OptVarName : /* empty */ {
$$ = new std::string();
}
| ':' VARNAME {
$$ = $2;
};
DagArgListNE : Value OptVarName {
$$ = new std::vector<std::pair<Init*, std::string> >();
$$->push_back(std::make_pair($1, *$2));
delete $2;
}
| DagArgListNE ',' Value OptVarName {
$1->push_back(std::make_pair($3, *$4));
delete $4;
$$ = $1;
};
DagArgList : /*empty*/ {
$$ = new std::vector<std::pair<Init*, std::string> >();
}
| DagArgListNE { $$ = $1; };
RBitList : INTVAL {
$$ = new std::vector<unsigned>();
$$->push_back($1);
} | INTVAL '-' INTVAL {
if ($1 < 0 || $3 < 0) {
err() << "Invalid range: " << $1 << "-" << $3 << "!\n";
exit(1);
}
$$ = new std::vector<unsigned>();
if ($1 < $3) {
for (int i = $1; i <= $3; ++i)
$$->push_back(i);
} else {
for (int i = $1; i >= $3; --i)
$$->push_back(i);
}
} | INTVAL INTVAL {
$2 = -$2;
if ($1 < 0 || $2 < 0) {
err() << "Invalid range: " << $1 << "-" << $2 << "!\n";
exit(1);
}
$$ = new std::vector<unsigned>();
if ($1 < $2) {
for (int i = $1; i <= $2; ++i)
$$->push_back(i);
} else {
for (int i = $1; i >= $2; --i)
$$->push_back(i);
}
} | RBitList ',' INTVAL {
($$=$1)->push_back($3);
} | RBitList ',' INTVAL '-' INTVAL {
if ($3 < 0 || $5 < 0) {
err() << "Invalid range: " << $3 << "-" << $5 << "!\n";
exit(1);
}
$$ = $1;
if ($3 < $5) {
for (int i = $3; i <= $5; ++i)
$$->push_back(i);
} else {
for (int i = $3; i >= $5; --i)
$$->push_back(i);
}
} | RBitList ',' INTVAL INTVAL {
$4 = -$4;
if ($3 < 0 || $4 < 0) {
err() << "Invalid range: " << $3 << "-" << $4 << "!\n";
exit(1);
}
$$ = $1;
if ($3 < $4) {
for (int i = $3; i <= $4; ++i)
$$->push_back(i);
} else {
for (int i = $3; i >= $4; --i)
$$->push_back(i);
}
};
BitList : RBitList { $$ = $1; std::reverse($1->begin(), $1->end()); };
OptBitList : /*empty*/ { $$ = 0; } | '{' BitList '}' { $$ = $2; };
ValueList : /*empty*/ {
$$ = new std::vector<Init*>();
} | ValueListNE {
$$ = $1;
};
ValueListNE : Value {
$$ = new std::vector<Init*>();
$$->push_back($1);
} | ValueListNE ',' Value {
($$ = $1)->push_back($3);
};
Declaration : OptPrefix Type ID OptValue {
std::string DecName = *$3;
if (ParsingTemplateArgs) {
if (CurRec) {
DecName = CurRec->getName() + ":" + DecName;
} else {
assert(CurMultiClass);
}
if (CurMultiClass)
DecName = CurMultiClass->Rec.getName() + "::" + DecName;
}
addValue(RecordVal(DecName, $2, $1));
setValue(DecName, 0, $4);
$$ = new std::string(DecName);
};
BodyItem : Declaration ';' {
delete $1;
} | LET ID OptBitList '=' Value ';' {
setValue(*$2, $3, $5);
delete $2;
delete $3;
};
BodyList : /*empty*/ | BodyList BodyItem;
Body : ';' | '{' BodyList '}';
SubClassRef : ClassID {
$$ = new SubClassRefTy($1, new std::vector<Init*>());
} | ClassID '<' ValueListNE '>' {
$$ = new SubClassRefTy($1, $3);
};
ClassListNE : SubClassRef {
$$ = new std::vector<SubClassRefTy>();
$$->push_back(*$1);
delete $1;
}
| ClassListNE ',' SubClassRef {
($$=$1)->push_back(*$3);
delete $3;
};
ClassList : /*empty */ {
$$ = new std::vector<SubClassRefTy>();
}
| ':' ClassListNE {
$$ = $2;
};
DeclListNE : Declaration {
getActiveRec()->addTemplateArg(*$1);
delete $1;
} | DeclListNE ',' Declaration {
getActiveRec()->addTemplateArg(*$3);
delete $3;
};
TemplateArgList : '<' DeclListNE '>' {};
OptTemplateArgList : /*empty*/ | TemplateArgList;
OptID : ID { $$ = $1; } | /*empty*/ { $$ = new std::string(); };
ObjectName : OptID {
static unsigned AnonCounter = 0;
if ($1->empty())
*$1 = "anonymous."+utostr(AnonCounter++);
$$ = $1;
};
ClassName : ObjectName {
// If a class of this name already exists, it must be a forward ref.
if ((CurRec = Records.getClass(*$1))) {
// If the body was previously defined, this is an error.
if (!CurRec->getValues().empty() ||
!CurRec->getSuperClasses().empty() ||
!CurRec->getTemplateArgs().empty()) {
err() << "Class '" << CurRec->getName() << "' already defined!\n";
exit(1);
}
} else {
// If this is the first reference to this class, create and add it.
CurRec = new Record(*$1);
Records.addClass(CurRec);
}
delete $1;
};
DefName : ObjectName {
CurRec = new Record(*$1);
delete $1;
if (!CurMultiClass) {
// Top-level def definition.
// Ensure redefinition doesn't happen.
if (Records.getDef(CurRec->getName())) {
err() << "def '" << CurRec->getName() << "' already defined!\n";
exit(1);
}
Records.addDef(CurRec);
} else {
// Otherwise, a def inside a multiclass, add it to the multiclass.
for (unsigned i = 0, e = CurMultiClass->DefPrototypes.size(); i != e; ++i)
if (CurMultiClass->DefPrototypes[i]->getName() == CurRec->getName()) {
err() << "def '" << CurRec->getName()
<< "' already defined in this multiclass!\n";
exit(1);
}
CurMultiClass->DefPrototypes.push_back(CurRec);
}
};
ObjectBody : ClassList {
for (unsigned i = 0, e = $1->size(); i != e; ++i) {
addSubClass((*$1)[i].first, *(*$1)[i].second);
// Delete the template arg values for the class
delete (*$1)[i].second;
}
delete $1; // Delete the class list...
// Process any variables on the set stack...
for (unsigned i = 0, e = LetStack.size(); i != e; ++i)
for (unsigned j = 0, e = LetStack[i].size(); j != e; ++j)
setValue(LetStack[i][j].Name,
LetStack[i][j].HasBits ? &LetStack[i][j].Bits : 0,
LetStack[i][j].Value);
} Body {
$$ = CurRec;
CurRec = 0;
};
ClassInst : CLASS ClassName {
ParsingTemplateArgs = true;
} OptTemplateArgList {
ParsingTemplateArgs = false;
} ObjectBody {
$$ = $6;
};
DefInst : DEF DefName ObjectBody {
if (CurMultiClass == 0) // Def's in multiclasses aren't really defs.
$3->resolveReferences();
// If ObjectBody has template arguments, it's an error.
assert($3->getTemplateArgs().empty() && "How'd this get template args?");
$$ = $3;
};
// MultiClassDef - A def instance specified inside a multiclass.
MultiClassDef : DefInst {
$$ = $1;
// Copy the template arguments for the multiclass into the def.
const std::vector<std::string> &TArgs = CurMultiClass->Rec.getTemplateArgs();
for (unsigned i = 0, e = TArgs.size(); i != e; ++i) {
const RecordVal *RV = CurMultiClass->Rec.getValue(TArgs[i]);
assert(RV && "Template arg doesn't exist?");
$$->addValue(*RV);
}
};
// MultiClassBody - Sequence of def's that are instantiated when a multiclass is
// used.
MultiClassBody : MultiClassDef {
$$ = new std::vector<Record*>();
$$->push_back($1);
} | MultiClassBody MultiClassDef {
$$->push_back($2);
};
MultiClassName : ID {
MultiClass *&MCE = MultiClasses[*$1];
if (MCE) {
err() << "multiclass '" << *$1 << "' already defined!\n";
exit(1);
}
MCE = CurMultiClass = new MultiClass(*$1);
delete $1;
};
// MultiClass - Multiple definitions.
MultiClassInst : MULTICLASS MultiClassName {
ParsingTemplateArgs = true;
} OptTemplateArgList {
ParsingTemplateArgs = false;
}'{' MultiClassBody '}' {
CurMultiClass = 0;
};
// DefMInst - Instantiate a multiclass.
DefMInst : DEFM ID { CurDefmPrefix = $2; } ':' SubClassRef ';' {
// To instantiate a multiclass, we need to first get the multiclass, then
// instantiate each def contained in the multiclass with the SubClassRef
// template parameters.
MultiClass *MC = MultiClasses[$5->first->getName()];
assert(MC && "Didn't lookup multiclass correctly?");
std::vector<Init*> &TemplateVals = *$5->second;
delete $5;
// Verify that the correct number of template arguments were specified.
const std::vector<std::string> &TArgs = MC->Rec.getTemplateArgs();
if (TArgs.size() < TemplateVals.size()) {
err() << "ERROR: More template args specified than multiclass expects!\n";
exit(1);
}
// Loop over all the def's in the multiclass, instantiating each one.
for (unsigned i = 0, e = MC->DefPrototypes.size(); i != e; ++i) {
Record *DefProto = MC->DefPrototypes[i];
// Add the suffix to the defm name to get the new name.
assert(CurRec == 0 && "A def is current?");
CurRec = new Record(*$2 + DefProto->getName());
addSubClass(DefProto, std::vector<Init*>());
// Loop over all of the template arguments, setting them to the specified
// value or leaving them as the default if necessary.
for (unsigned i = 0, e = TArgs.size(); i != e; ++i) {
if (i < TemplateVals.size()) { // A value is specified for this temp-arg?
// Set it now.
setValue(TArgs[i], 0, TemplateVals[i]);
// Resolve it next.
CurRec->resolveReferencesTo(CurRec->getValue(TArgs[i]));
// Now remove it.
CurRec->removeValue(TArgs[i]);
} else if (!CurRec->getValue(TArgs[i])->getValue()->isComplete()) {
err() << "ERROR: Value not specified for template argument #"
<< i << " (" << TArgs[i] << ") of multiclassclass '"
<< MC->Rec.getName() << "'!\n";
exit(1);
}
}
// Ensure redefinition doesn't happen.
if (Records.getDef(CurRec->getName())) {
err() << "def '" << CurRec->getName() << "' already defined, "
<< "instantiating defm '" << *$2 << "' with subdef '"
<< DefProto->getName() << "'!\n";
exit(1);
}
Records.addDef(CurRec);
CurRec->resolveReferences();
CurRec = 0;
}
delete &TemplateVals;
delete $2;
CurDefmPrefix = 0;
};
Object : ClassInst {} | DefInst {};
Object : MultiClassInst | DefMInst;
LETItem : ID OptBitList '=' Value {
LetStack.back().push_back(LetRecord(*$1, $2, $4));
delete $1; delete $2;
};
LETList : LETItem | LETList ',' LETItem;
// LETCommand - A 'LET' statement start...
LETCommand : LET { LetStack.push_back(std::vector<LetRecord>()); } LETList IN;
// Support Set commands wrapping objects... both with and without braces.
Object : LETCommand '{' ObjectList '}' {
LetStack.pop_back();
}
| LETCommand Object {
LetStack.pop_back();
};
ObjectList : Object {} | ObjectList Object {};
File : ObjectList;
%%
int yyerror(const char *ErrorMsg) {
err() << "Error parsing: " << ErrorMsg << "\n";
exit(1);
}